The present invention relates to cutting tools or drill bits, and more particularly, to cutting tools which are used in hammering, percussive, or rotary boring or drilling applications in concrete, aggregate, masonry or the like material.
When drilling concrete, aggregate or the like materials, generally three types of cutting tools or bits are used. These bits can be defined as hammer bits, percussive bits, and rotary masonry bits. All of the bits have one thing in common: A need to exit the created debris from the drilled hole. In order to remove debris from the hole, the flute is important in exiting the debris from the hole. Parameters which are important in designing debris channels are a base surface, a side wall surface as well as a web or back surface which connects the base surface with the side wall surface axially along the longitudinal axis of the bit. Equally important is the angle the surfaces make with respect to one another and to the longitudinal axis.
Existing hammer, percussive and rotary masonry bits, while being provided with different types of flute design, do not optimumly eject debris from the forming hole. Also, several of the flutes are worked such as by grinding in order to provide proper orientation of the shank for insertion of the inserts into the shank.